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        Alternative Energy – Why Does It Matter?

When reserves of coal, as an example, will be used up in energy production it will not be replenished by the
nature in any way. Coal is the type of non-renewable energy. Wind on the other hand is abundant and will never
face an end like the former one. The continuous availability makes it one of the most competitive renewable
energy sources today. When used in a way that does not affect or disturb the nature and eco-system it is a
sustainable form of energy source. That’s the aim of present day’s slogan of ‘green technology’.

Alternative energy offers a number of benefits including,

- Most of the sources are plenty in nature and are regularly replenished.
- Low risk or environmental pollution mainly soil, water and air.
- As emissions of greenhouse gases are very much restrained, therefore it plays a positive role in
global warming.Continuous development of technologies will ensure higher and better efficiency
of equipments and design in the production and maintenance of energy plants, offering low costs
energy supply to households, industries and vehicles.

Some of the potential sources of alternative energy are:wind energy, solar energy, hydro power,
geothermal energy, biomass, nuclear energy(??).

About 13% of primary energy comes from renewables, with most of this coming from traditional
biomass like wood-burning. Hydropower is the next largest source, providing 2 – 3%, and modern
technologies like geothermal, wind, solar, and marine energy together produce less than 1% of
total world energy demand.

Fast-growing renewables like wind and solar experienced very high annual growth wind with 48%
leading over solar (28%).

Hydropower: Using the river currents to generate electricity

Hydropower can successfully reduce greenhouse gases emissions to the atmosphere. In Brazil,
80% of electricity is hydropower
which accounts for only 10% of the country’s total carbon dioxide
(CO2) emissions. The rate is four times less than the world average. Hydroelectricity therefore offers
a huge potentials for many developing countries. But it can at the same time cause concerns for the
environments as building dams can drastically affect the entire ecosystem and cause cultural damages.

The famous Chinese “
Three Gorges Dam” which spans the Yangtze River is the world’s largest
hydroelectric dam till to date. While the economic benefits are in priority, behind the scenes a total
of 1.13 million people will be displaced, many species will be put on the verge of extinction like the
Chinese River dolphin ‘Baiji’. Other effects like lack of silt transport to the Yangtze Delta could result
in erosion and sinking of coastal areas. Therefore hydroelectric power benefits via reducing greenhouse
gases emissions in one hand but destroys the surrounding ecosystem on the other hand.

Wind power and carbon dioxide (CO2) emissions:

Wind power is certainly going to be in the leading position among all the renewable energy sources
in the coming years. The market is expanding faster than ever thought. While in 1995 total power generation
was 4,800 MW (megawatt) it multiplied 12-times to 59,000 MW in 2005 (Greenpeace, 2006).
Offshore and
high altitude areas are more preferable for wind farms because of strong winds.
Offshore stations experience
mean wind speeds at 80 m that are about 90% greater than over land on average (Archer & Jacobson, 2005).
As the wind speed increases, power output increases dramatically and shortens the peak of carbon dioxide
(CO2) emissions in the graph.As the efficiency of wind turbines is increasing from year to year because of
better equipment design and taller turbines, production cost can go as low as 3 to 4 Euro cents per kWh
(kilowatt) by 2020.

Spain’s Solar Tower

The solar thermal power plant outside Seville in southern Spain is very recent development harnessing Sun’s
rays. It is Europe’s first commercial solar thermal power plant. The plant is called
PS – 10.

The plant generates
11 MW of electricity that can power up to 6,000 homes without emitting a single puff of
greenhouse gases. The receiver in 115 m  solar tower after receiving reflected sun rays from 600 solar
reflectors, which are on the ground and each reflectors (heliostats)120 sq m (square meters) in size, converts
the concentrated solar energy into steam. The steam is stored in tanks and used to drive turbines to produce
electricity. Although currently the power is three times more expensive than conventional sources but certainly
as technologies are developing fast it can be hoped that the price will fall soon. The bottom line is no emissions
and no dependency on petroleum.

Bioenergy and Germany

Germany is currently the leading country with fast growing bioenergy industry. 2,700 biogas systems were
installed in thecountry by the end of 2005 with an
overall electrical capacity of 650 MW. The raw materials come
from agricultural wastes, commercial wastes or specially grown energy crops. Biogas, methane, is produced by
fermenting the biomass. Benefits lie in the reduced CO2 emissions to the atmosphere. Upgrading the quality to
that of natural gas it will be possible in near future to use biogas in the fuel sector either to substitute or
supplement natural gas.

Risk of Nuclear plants

The leak of radioactively contaminated water from the world’s largest nuclear power plant in Kashiwazaki in
Japan July this year is the most recent example of risk using nuclear power after 1986 Chernobyl disaster. The
generations in
Chernobyl are still bearing the aftermath of the explosion. Where the Chernobyl disaster might
have been caused due to faulty reactor design or operators mistake, the Japan spills are completely because of
natural cause. A 6.8 magnitude earthquake simply rocked the nuclear power plant. This opens up a window
where it can be seen that either a man-made fault or a natural cause can easily put such sophisticated
installations under unpremeditated risks.

In the Line of Industrialization

South Asia, house of a quarter of the world’s population (1.3 billion currently) is currently experiencing a rapid
growth in energy demand in order to keep pace with economic growth and industrialization. The total primary
energy supply in the region, including renewable energy, is expected to increase to 1411 MTOE (million tonnes
of oil equivalent) in 2010/2011, with biomass accounting for 28% of the total energy consumption (Kumar, 2000).

In conclusion,

Alternative energy sources offer vast potentials to supply enough energy for future demands without any or very
limited emission of greenhouse gases to the atmosphere. As new countries are joining in the line of
industrialization, alternative energy sources ensure a cleaner and healthier environment for our planet. Ongoing
research will definitely bring forth new technologies which can reduce the energy costs substantially and benefit
us en masse. Therefore it is going to be the next generations ‘
Green Energy Sources’.


                                                                                                                                             Khaled Mahmud Shams
                                                                                                                                                             Salzburg
                                                                                                                                                              30.09.07



References:

Archer C.L. & Jacobson M.Z. (2005): Evaluation of Global Wind Power
                                                      (
http://www.stanford.edu/group/efmh/winds/global_winds.html).
Greenpeace (2006): Global Wind Energy
                                   (
http://www.greenpeace.org/international/press/reports/globalwindenergyoutlook)

Kumar A. (2000): Energy Scenario in South Asia, Energy Technology news, Issue 1
                   (
http://www.teriin.org/opet/articles/art1.htm)

Renewables Made in Germany
           (
http://www.renewables-made-in-germany.com/en/biogas/)

Renewable Energy -
Wikipedia

Shukman D. (2007): Power Station Harnesses Sun’s Rays
                         (
http://news.bbc.co.uk/2/hi/science/nature/6616651.stm)
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____________________________________________________________________________________________________________________________________________
  Alternative Energy
A wind turbine. This 3 bladed turbine is the most common design
of modern wind turbines. Source:
Wikipedia